I've been searching about this issue (in Japanese and English version) but still didn't find any solutions yet.
My PC environment :
Windows 8.1 Pro (Japanese) 64-bit, IE 11, IME 2012, Office 2013
Issue :
When I open IE 11 and access to Sharepoint or Google sites, the IME bar suddenly disable. I can keep writing in Japanese in Outlook but not in Google search, or Sharepoint forms. Also when I open Notepad, i cannot write in Japanese anymore. I can see [J] icon at bottom right of my PC but the IME icon shows [X] with "IME is disable" message with it.
At first i thought the issue is in IME 2012 but when i use Mozilla or Chrome, the issue not occur. So I think this must be one of IE 11 bug.
Right now I disable IE 11 in my PC and use Chrome as default web browser. Just that my company systems is based on Microsoft products so whenever I view some systems with Chrome the result is disappointing. I hope someone notice this post and can give some opinions.
Thank you.